Transcript for Valedictorian Accused of Murdering Mother: First Day of Trial

Thank you so much. Let's bring in dan abrams. Dan, we heard john say on day one of this trial, the prosecution played the 911 case. We heard a snippet of it there. It's pretty powerful stuff, but the husband of the murder victim you that hear on that tape is in court supporting the accused victim? That's right. It's not like you have the person on trial calling 911 and the jurors will want to listen to every intonation and how obsessed the person seems, et cetera. Here, it's really setting the stage for the evidence to come. And it's key, as you've been saying about this case, the defense is not saying, yes, he killed here as a result of abuse, but they're saying Have they presenteded any alibi? So far, we're hearing the prosecution's case. And this was a good day for the prosecution, no question about it. The wounds on the hands are the best evidence for prosecutors. The question is going to be, can prosecutors cross over from, yeah, this guy could have done it to proof beyond ronald doubt that he did do it. And I think that's going to be the challenge for prosecutors here. Because, they're certainly going to have evidence that there's a reason he might have done it. There are questions. There are these injuries on his hands. There was some blood found in the home. There's definitely, you know, a motive here. But can they take to that next level is the question, I think, they're going to have trouble doing. I have to say, somebody reading into the history of this case, not only was the murderer arrested for attacking her son, but apparently, since the time he was 9 years old, he was threatening to kill him. Wasn't there a crime committed. Didn't somebody fail the little boy in this case? No question. But remember, now, that is in the past because that's not what his defense was. He's saying he simply was not there. So this won't even be relevant? No, it's relevant to the prosecution's motive. The prosecution is saying this was the motive. But the defense is saying, i wasn't there. So this is not that kind of defense which makes this an incredible bizarre case. Because that helps the defense on one hand, but that's the prosecution's theory on the other. A literally sad case all the way around. Yeah. All right, dan. We'll check in with sam

This transcript has been automatically generated and may not be 100% accurate.

Valedictorian Accused of Murdering Mother: Jurors Hear 911 Tapes

John Muller reports on the first day of the trial of Jeffery Pyne.

High School Valedictorian Murder Trial Begins

Jeffrey Pyne, 22, is accused of killing his own mother.

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